Neil Stanley goes to bed each night knowing he will wake up a little richer. All over the world, the clicks of computer mice are depositing a few more pounds into his account. His secret is that he was smart enough to ask: what's in a name?

Stanley is a trader in domain names, the addresses of websites which commonly follow 'www' and end with '.com' or '.co.uk'. Once a banker at Goldman Sachs, he now has a different portfolio of lucrative investments including bridalfashion.co.uk, onlinecareers.co.uk, schoolguide.co.uk, sendingflowers.co.uk and impotency.co.uk.

He is one of a growing band of cyber-speculators able to make a living from buying and selling domain names at a substantial profit. No effort or expertise in building websites is required. Instead, a PC with broadband connectivity and an eye for a popular generic domain is enough to draw traffic and unlock a fortune. Recently Stanley was involved in a deal which registered a domain name for almost nothing and sold it for $40,000 a few weeks later.

'It's amazing how many people go to the address bar and type in a generic name instead of going to Google,' said the 44-year-old from Bath. 'If you've got mortgages.co.uk, you've got a licence to print money. It's an industry in its infancy and there's a bit of a gold rush on at the moment. It's amazing that the UK hasn't really woken up to it yet.

'The analogy is real estate. The internet got invented and all the land is being bought up. In 10 years' time any word you can think of will be taken: all the real estate will be gone. If one day someone wants to build a skyscraper on it, you've made a fortune.'

There are about 140 million domain names worldwide. The 6.6 million with the 'co.uk' suffix, a total swelling by 140,000 per month, are registered with an organisation called Nominet. But most trading is done in a secondary market via specialist websites, such as whois.sc, which can show whether a name has already been taken, suggest close alternatives or offer a route to the existing owner in case they are willing to sell.

Stanley acquired kids.co.uk and is planning to make it a non-profit site for children, but leaves the majority of his domain names sitting idle, or 'parked'. This means that they are hosted by a specialist website as a simple, customised template containing relevant adverts. Every time someone visits the page and clicks on one of the adverts, the name owner and the website share revenue.

'Whenever I register or buy a domain name, the first thing I do is park it,' said Stanley, who is writing a book on the subject. 'Anyone who then types in that name will see the web page and, if they click on an ad, it generates money. I registered noworryloans.co.uk last autumn and it probably earns £10 a week on its own. My whole portfolio is bringing in hundreds of pounds every week without me touching it, and some people are creaming in thousands. My conviction is that this going to become mainstream because it's so easy.'

Sedo, or 'Search Engine for Domain Offers', claims to have the world's biggest database of names for sale, with more than 10.5 million listings. Its total sales in 2007 amounted to £37m. In Britain it has overseen the sale of sport.co.uk for £135,000 and mobile.co.uk for £120,000. Sedo also 'parks' more than 3 million domains and paid out £25m to customers last year.

Nora Nanayakkara, business development director of the company, said: 'We've spoken to people who are now doing this as a full-time career. People are putting their kids through school on the money they make.'

Last month, cruises.co.uk set a British record when it fetched £560,000. But, America is one step ahead. Kevin Ham, dubbed 'the most powerful dotcom mogul you've never heard of', is estimated to have stockpiled 300,000 domains that generate $70m a year. He even struck a deal with the government of Cameroon so that when users mistakenly type '.cm' instead of '.com', he gets a slice of the cake.